Antislippage means for wire tensioning apparatus



July 14, 1970 BROWN 3,520,492

ANTISLIPPAGE MEANS FOR WIRE TENSIONING APPARATUS Filed April 4, 1968 Mm?! 14/ 5mm,

3,520,492 ANTISLIPPAGE MEANS FOR WIRE TENSIONING APPARATUS Maurice H. Brown, Palos Heights, Ill., assignor to Azonic Products, Inc., Palos Heights, III., a corporation of Illinois Filed Apr. 4, 1968, Ser. No. 718,775 Int. Cl. B65h 59/16 US. Cl. 242-455 2 Claims ABSTRACT OF THE DISCLOSURE An apparatus for applying tension to a continuous wire as the wire is unwound from a reel and wound onto coils or the like, including a band brake wire tensioning assembly having a pulley with a groove formed around its periphery to receive one or more loops of the wire. The width of the groove is considerably greater than the diameter of the wire and has a generally concave base surface. An elastic band is positioned in the groove in tight engagement with the concave surface thereof and located alongside the wire so as to contact the wire and prevent slippage of the wire during winding operations.

SUMMARY OF THE INVENTION This invention is concerned generally with means for preventing the slippage of wire passing around a tensioning device and more specifically with means to prevent slippage of wire relative to the pulley of a band brake wire tensioning device.

An object of this invention is an antislip device that can be easily installed on and removed from a wire tensioning pulley.

Another object is an antislip device that will not interfere with the normal tensioning of the wire.

Another object is an antislip device that will remain in contact with the wire being wound around the pulley.

Another object is an antislip device that is adjustable to pulleys of various sizes.

Other objects will be found in the following specification, claims, and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 one embodiment of the antislip means of this invention is shown mounted on a wire tensioning apparatus having a frame 10, a clutch-type tensioning mechanism 12, a band brake tensioning assembly 14, a brake adjusting means 16 and several wire directing idler pulleys such as indicated at 18 and 20. A wire 24 is shown being pulled through the apparatus by the winding action of a bobbin or spool 26 driven by a suitable wind- 'ing machine, not shown.

United States Patent Ofice 3,520,492 Patented July 14, 1970 The wire 24 first enters the clutch-type tensioning mechanism 12 and then is looped one or more times around the band brake tensioning assembly 14. The band brake tensioning means includes a pulley 30 having an outward opening groove 32 formed in the periphery thereof. The groove 32 has a generally concave bottom surface 34 and has a width considerably greater than the diameter of the wire 24. The pulley 30 is rotatably mounted on stub shaft 36 which is fastened to frame 10. The brake band wheel 30 also has a circumferential brake band surface 38. A friction brake band 40 is draped around this circumferential braking surface 38 and is attached at its ends to the frame 10 and a braking arm 42 by lugs 44 and 46, respectively. The braking arm 42 is also rotatably mounted on the stub shaft 36.

As the wire 24 is pulled through the apparatus in the direction shown in FIG. 1, the frictional engagement of the wire 24 with the concave bottom surface 34 of the groove 32 will tend to cause the brake band Wheel 30 to rotate in a clockwise direction as viewed in FIG. 1. Further, as the arm 42 is rotated in a clockwise direction, the force of engagement of the friction band 40 with the circumferential braking surface 38 is increased. A spring 48 is provided to urge the arm 42 in a clockwise direction as viewed in FIG. 1, to thereby increase the force of engagement between the friction band 40 and the circumferential braking surface 38. This spring is connected through a screw thread 50 which can be moved up and down relative to the frame 10 to increase or decrease the amount of engagement of the friction band 40 with the braking surface 38.

To reduce slippage of the wire 24 relative to the band brake wheel, an elastic band such as a rubber band 52 is fitted over the pulley 30 in the groove 32 in contact with the concave bottom surface 34 thereof. The elastic band is selected so that it must be stretched to fit around the pulley and therefore bears tightly against the concave surface of the groove. Because of the concave surface of the groove and the centrifugal force caused by the rotation of the pulley, both the elastic band and wire will generally gravitate towards the low point of the groove and therefore contact each other to provide additional friction to prevent slippage of the wire.

FIG. 3 shows a modified elastic band in the form of an O-ring 54. It has been found that an O-ring functions to prevent slippage of the Wire in substantially the same manner as a common rubber band when the inside diameter of the unstretched O-ring is less than the outside minimum diameter of the groove 32. That is to say, the O-ring must be stretched to fit over the pulley and is in a stretched condition when it is in contact with the lowest portion of the bottom surface of the pulley groove. Upon rotation of the pulley, the O-ring and the wire will move into contact with each other at the low point of the groove.

Whereas, several forms of the invention have been shown and described, it should be understood that suitable other additions, alterations, and variations may be made without departing from the inventions fundamental theme. Therefore, the scope of the invention should be limited only by the claims appended hereto.

I claim:

1. In a device adapted to apply tension to a continuous wire-like member being drawn therethrough, which device includes a tensioning pulley having a radially, outwardly opening groove formed in the periphery thereof to receive said wire-like member wound around the pulley, said groove having a concave bottom surface adapted to be contacted by said wire-like member with the diameter of said concave bottom surface being at least several times the diameter of said wire-like member, and an elastic band positioned in said groove and tightly engaging the concave surface throughout the circumferential extent of said groove and contacting said wire-like member with said elastic band having a maximum cross-sectional dimension at least several times smaller than the diameter of said concave bottom surface of said groove.

2. The structure of claim 1 further characterized in References Cited UNITED STATES PATENTS 2,073,818 3/1937 Viens 242l55 X 2,924,397 2/ 1960 Heppner. 3,022,025 2/ 1962 Saxl. 3,327,964 6/ 1967 Nussbaumer 242155 3,352,511 11/1967 Wiggins.

STANLEY N. GILREATH, Primary Examiner 

